CN101535565B - A method and equipment for the evaporation of black liquor that is obtained from a digestion process during the production of cellulose pulp - Google Patents
A method and equipment for the evaporation of black liquor that is obtained from a digestion process during the production of cellulose pulp Download PDFInfo
- Publication number
- CN101535565B CN101535565B CN200780041461.1A CN200780041461A CN101535565B CN 101535565 B CN101535565 B CN 101535565B CN 200780041461 A CN200780041461 A CN 200780041461A CN 101535565 B CN101535565 B CN 101535565B
- Authority
- CN
- China
- Prior art keywords
- evaporation
- black liquor
- evaporation stage
- heat exchanger
- stage
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D1/00—Evaporating
- B01D1/26—Multiple-effect evaporating
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
- B01D3/10—Vacuum distillation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D5/00—Condensation of vapours; Recovering volatile solvents by condensation
- B01D5/0033—Other features
- B01D5/0036—Multiple-effect condensation; Fractional condensation
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/10—Concentrating spent liquor by evaporation
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Paper (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
The invention concerns a method and equipment for the evaporation of hot black liquor obtained from a digestion process during the production of cellulose pulp, where the black liquor is led to a multistage evaporation line with at least five evaporation stages. According to the invention, the black liquor (11, 10) that is to undergo evaporation in the evaporation line is cooled in at least one heat exchange process in a heat exchanger (HE1) against partially evaporated black liquor (20, 21 ) that has undergone evaporation in at least one stage (I). The black liquor that is to undergo evaporation is cooled and the partially evaporated black liquor is heated by at least 5-10 <0>C. The risk for the formation of foam is reduced through the invention, as is the separation of methanol. The greater part of the work of evaporation takes place at low temperature and at the lowest level of dry matter content in the liquor, which also suppresses encrustation in the stage.
Description
Technical field
The present invention relates to a kind of method that is used for evaporating the black liquor (black liquor) that during the cellulose pulp manufacturing, obtains from digestion process, wherein, preamble according to claim 1 is described, and black liquor is led to the multistage evaporation pipeline with at least five evaporation stages (stage).The invention still further relates to a kind ofly, in this equipment, can use the method according to this invention as the equipment that claim 11 limited.
Background technology
The main purpose of above-mentioned evaporation is that moisture is evaporated from black liquor, makes black liquor can be used as the fuel in the alkali stove (soda boiler).Live steam (fresh steam) amount that the water yield that realization this purpose can make per unit be evaporated can run out possible minimum, thereby make the loss of the digestion chemicals that can reuse and wood materials as far as possible little, and the moisture that is evaporated can be reused in the processing procedure of pulp mill.
Usually, remain from the dry matter content in the black liquor of digestion equipment (digestion plant) about 15%, and before burning desired dry matter content greater than 60%.This means, obtain dry per ton and will remove about 5 tons water.
The least possible for the consumption that keeps steam, use processing with at least five evaporation stages, in this is handled, only supply with live steam at last the highest evaporation stage of the dry matter content of black liquor.The steam (liquid vapour) of discharging is guided subsequently in turn through other levels.The reduction of the steam consumption in having the evaporation pipeline of five evaporation stages is about 75% of steam consumption when only using an evaporation stage.If use six evaporation stages (evaporation pipeline), then this reduction will be 80%.By at different levels, using steam, can farthest utilize the temperature difference to conduct heat effectively, until high negative pressure occurs in the first order, black liquor has carried out the rising first time of its dry matter content level in this first order.Usually, in three of beginning or four evaporation stages, keep negative pressure, making the black liquor be in low temperature and low concentration can realize relatively large evaporation.Thereby, in evaporation stage, in 50-140 ℃ temperature range, carry out the vaporization (boil off) of black liquor.Use dissimilar hyperconcetration devices that black liquor is further evaporated at the end of evaporation stage, and usually by sneaking into the blend step the preceding from the ashes in the alkali stove, the level that makes dry matter content is just above 80%.
Before black liquor is led to evaporation stage, can heat black liquor usually, so that improve the thermal efficiency.For example, at books " Lutindunstning och biprodukter " (" liquid evaporation and accessory substance ", Yrkesbok, Y-211, ISBN 91-7322-042-6 is published by Sweden forest industry federation (SwedishForest Industries Federation)) in described how by the black liquor in Kastner (Kestner) evaporimeter the Steam Heating spiral preheating device of discharging from the condensate recover.Subsequently, the black liquor that will evaporate in evaporation stage 1 is guided through first heat exchanger that is connected to evaporation stage 3, wherein the condensation vapour (condensate steam) from evaporation stage 3 adds hot black liquor, and black liquor is guided through second heat exchanger that is connected to evaporation stage 2 subsequently, and wherein the condensation vapour from evaporation stage 2 adds hot black liquor in second heater stages.
From patent documentation EP 485375 (being equivalent to US4963231), learn a kind of processing procedure, in this processing procedure, come after the evaporation of autocondensation presteaming device (condensing pre-steamer) liquid can with in the middle of two evaporation stages, carry out heat exchange from the hotter of subsequently evaporation stage and by evaporated liquid more.This processing procedure is intended to improve inherently the efficient of evaporation pipeline, and wherein, this liquid carries out evaporating at evaporation stage before the heat exchange being used to.The purpose of this process is the steam by the low value (low-value) of black liquor cooling in condensation presteaming device that will evaporate, rather than cools off and be condensate in the steam of the low value in the water cooler.Here, the heat exchange action between the liquid is, heats the black liquor that will evaporate in evaporation stage subsequently by established heated liquid in evaporation stage subsequently.
Summary of the invention
The present invention aims to provide a kind of improved black liquor vaporizing mode, and it has the following advantages:
Demand to live steam is lower, has improved heat-economy;
By before evaporation, black liquor being cooled off, improve the separation of methyl alcohol, mix with the live steam evaporation vapour of avoiding being rich in methyl alcohol in any level (evaporation steam) lower with methanol content;
Substitute liquid flash (liquor flashing) has reduced to form foam in evaporation process risk by the cooling black liquor;
First evaporation stage carries out under low dry matter content level and low viscosity, and this has guaranteed the favourable heat transfer condition during first evaporation stage, thereby can the mounted area of heating surface of optimal;
Between the black liquor of black liquor that will evaporate and part evaporation, carry out the recirculation of heat energy, thereby can in the evaporation pipeline, utilize the heat of black liquor subsequently, and do not have the loss of temperature grade;
By (saponified, fractionation of fatty hydrochlorate under low solubility soap) can improve the separation from the soap of the liquid of confierophyte at low temperature and soap.
Description of drawings
Fig. 1 shows the of the present invention basic design of implementing between two evaporation stages;
Fig. 2 shows the present invention who implements between three evaporation stages;
Fig. 3 shows the present invention who implements in the liquid that mixes connects, wherein the black liquor that will evaporate is guided in the mode of co-flow (cocurrent flow) in evaporation stage I, II, and the mode with reverse flow (countercurrent flow) is guided in evaporation stage III, IV;
Fig. 4 shows the present invention who implements in the evaporation stage of circulation in having; And
The modification of the present invention of circulation in Fig. 5 shows and has in evaporation stage I.
The specific embodiment
Fig. 1 shows the part of the equipment of the hot black liquor that obtains in order to evaporation from digestion process during the cellulose pulp manufacturing, wherein, black liquor is led to the multistage evaporation pipeline with at least five evaporation stages.
Each evaporation stage I, II have respectively and are used to supply the supply line 10,21 that keeps the black liquor first dry matter content level, that will evaporate, and each evaporation stage has respectively and is used for exporting the export pipeline 20,22 that has been evaporated and kept the black liquor of the higher second dry matter content level at this evaporation stage at least in part.
Each evaporation stage is respectively equipped with the supply line 3,2 that is used for supplying the steam that uses at this evaporation stage, keep first vapor (steam) temperature, and each evaporation stage be respectively equipped be used for exporting used at this evaporation stage, through the export pipeline 2,1 of the steam that keeps lower second vapor (steam) temperature behind this evaporation stage.
This there is shown two evaporation stage I, II, and wherein, employed steam is guided in the mode that is reverse flow with respect to black liquor stream and flows through pipeline 3,2,1, and wherein black liquor is guided and flows through pipeline 10,20,21,22.The steam that is discharged from and produced obtains hot water with mode condensation in surface condenser SC of routine from this surface condenser SC.
This there is shown the first heat exchanger unit HE1, it is connected to first evaporation stage, this first heat exchanger unit HE1 has first inlet and first outlet of the heated side of leading to heat exchanger unit, first inlet of this first heat exchanger unit is connected to the export pipeline 20 that is used to export from the black liquor of the first evaporation stage I, this first heat exchanger unit has second inlet that is connected to pipeline 11, and second outlet that is connected to pipeline 10, the cold side of this heat exchanger unit is led in described second inlet and second outlet, and second inlet 11 of this heat exchanger unit connects the hot black liquor that does not evaporate as yet in any evaporation stage.
The hot black liquor that obtains from digestion process during the cellulose pulp manufacturing evaporates by this way: make the hot black liquor that will in the evaporation pipeline, evaporate by with an evaporation stage in the evaporation pipeline in the black liquor of the evaporation of part of being evaporated at least in part carry out heat exchange and be cooled.
The black liquor that generally uses shown in Figure 1 and the temperature of steam below will be described, but should be clear and definite be in other are used, also to use other temperature.The black liquor that will evaporate was introduced in the pipeline 11 before arriving heat exchanger unit HE1, and remained 70 ℃ temperature.The black liquor that will evaporate in this heat exchanger be imported into pipeline 20 in the evaporated liquid of part of also in evaporation stage I, having evaporated carry out heat exchange and be cooled at least 5 ℃, be preferably at least 10 ℃, thereby reach 60 ℃ temperature.
Temperature remained about 55 ℃ evaporated liquid of part before being directed to evaporation stage II via pipeline 21, was heated to be equivalent to 65 ℃ temperature.The temperature of the vapor stream in the pipeline 3,2,1 remains 75 ℃, 65 ℃ and 55 ℃ respectively.
This connection makes that black liquor evaporates in first evaporation stage before, its temperature can be lowered, and its methyl alcohol is discharged prematurely, does not also have liquid by forming the risk that foam is converted into condensate.The major part of evaporation process is carried out in first evaporation stage, temperature in this evaporation stage is minimum, however, because the dry matter content of liquid is in low-level, it is acceptable low-level to make that the viscosity of liquid still can remain on, thereby guarantees the high coefficient of overall heat transmission.
Fig. 2 shows a kind of modification, in this modification, also be connected with the second heat exchanger unit HE2 between evaporation stage II, III, but in addition, this modification is identical with equipment shown in Figure 1.
The second heat exchanger unit HE2 is connected to the second evaporation stage II, this second heat exchanger unit has first inlet that is connected to pipeline 22 and first outlet that is connected to pipeline 23, the heated side of second heat exchanger unit is led in described first inlet and first outlet, wherein first of this second heat exchanger unit inlet is connected to the export pipeline 22 (this and claim 12 and not quite identical) that is used to export from the black liquor of the second evaporation stage II, and the second heat exchanger unit HE2 has second inlet that is connected to black liquor pipeline 12, and second outlet that is connected to pipeline 11, the cold side of second heat exchanger unit is led in described second inlet and second outlet, second inlet that wherein leads to second heat exchanger unit is connected to the hot black liquor that does not evaporate as yet in any evaporation stage, and wherein the hot black liquor that does not evaporate in any evaporation stage as yet at first was led to the cold side of second heat exchanger unit before being led to the cold side of the first heat exchanger unit HE1 via feed-line 11.
The hot black liquor that will evaporate carries out heat exchange and is cooled at least twice with black liquor that evaporated at least in part in first evaporation stage that evaporates pipeline and second evaporation stage, part evaporation.
Fig. 2 shows black liquor and directly is directed to evaporation stage I.In fact, in case when the temperature of black liquor was reduced to below 100 ℃, black liquor just can be led to and be used for storing or the black liquor groove of fractionation of fatty hydrochlorate (soap).Preferably, this storage is arranged on and is cooled to 60 ℃ (for the solubility of soap, this temperature is preferred temperature) afterwards, promptly is arranged on liquid chiller HE1 and reaches before the evaporation stage I afterwards.
This technology can be applied in a plurality of other levels, but in fact, a plurality of grades maximum number is 3-6, and wherein, the 3rd heat exchanger unit is connected to the 3rd evaporation stage in the mode identical with second heat exchanger unit being added to equipment among Fig. 2.The 3rd heat exchanger unit has first inlet and first outlet of the heated side of leading to the 3rd heat exchanger unit in the same way, wherein first of the 3rd heat exchanger unit inlet is connected to the export pipeline that is used to export from the black liquor of the 3rd evaporation stage, and the 3rd heat exchanger unit has second inlet and second outlet of the cold side of leading to the 3rd heat exchanger unit, wherein second of the 3rd heat exchanger unit inlet is connected to the hot black liquor that does not evaporate as yet in any evaporation stage, the described hot black liquor that does not evaporate in any evaporation stage as yet at first was led to the cold side of the 3rd heat exchanger unit before being led to the cold side of second heat exchanger unit and first heat exchanger unit via a plurality of feed-lines.
The hot black liquor that will evaporate carries out heat exchange with black liquor that evaporate at least in part, part evaporation and is cooled at least three times in first evaporation stage, second evaporation stage and the 3rd evaporation stage.
First evaporation stage, second evaporation stage and (being associated) the 3rd evaporation stage preferably are connected in the evaporation equipment with series system, wherein, the black liquor that will evaporate in described evaporation stage is led to second evaporation stage from first evaporation stage via the heated side of heat exchanger one by one, and be directed to the 3rd evaporation stage forward, and can be directed to the 4th evaporation stage forward.Be used to as follows carry out heat exchange with hot black liquor from first evaporation stage, second evaporation stage and the black liquor that can be the evaporation of part of the 3rd evaporation stage (even more evaporation stage): wherein the dry matter content level of the black liquor of part evaporation is increased from first evaporation stage to the second evaporation stage, and is further increased from second evaporation stage to the, three evaporation stages.
Fig. 3 shows another kind of modification of the present invention, in this modification, the black liquor that will evaporate be guided for and be connected to black liquor among the heat exchanger HE2 between evaporation stage III and the evaporation stage IV, part evaporation and carry out the heat exchange first time.After having carried out heat exchange for the first time, black liquor be guided for and be connected black liquor among the heat exchanger unit HE1 between evaporation stage II and the evaporation stage III, part evaporation and carry out the heat exchange second time.Evaporation stage I, II utilize co-flow to connect (black liquor that wherein will evaporate is same with vapor phase through the sequence of flow of evaporation stage) and connect.This fact more than has been described: the cooling of liquid need not to comprise whole evaporation processes.Preferably, the various black liquor grooves that are used for the fractionation of fatty hydrochlorate are arranged at after the heat exchanger unit HE1.In case fluid temperature is reduced to below 100 ℃, described black liquor groove also can be arranged on the position more early in the liquid stream.
Here, the first time of black liquor evaporation be in evaporation stage II with the similar mode of mode shown in Figure 2, use the black liquor that at first in heat exchanger unit HE1 and HE2, cools off to carry out.The liquid that is cooled carries out the evaporation process first time in evaporation stage II, after this, the black liquor of part evaporation is led to evaporation stage I.Black liquor pervaporation level II, I, part evaporation is led to evaporation stage III via preheater PH and via heat exchanger unit HE1 subsequently.
In the normal selection shown in Fig. 1 to Fig. 3, the inlet that leads to the heated side of heat exchanger is connected to the black liquor that will evaporate is sent to evaporation stage subsequently from an evaporation stage before feed-line.Use the black liquor and the hot black liquor of the evaporation of part of discharging the MPTS between two evaporation stages to carry out heat exchange in this way.
As shown in Figure 4, in the optional embodiment of described evaporation equipment, the part of the black liquor of part evaporation and heated black liquor are by pipeloop 21b and recirculation outside evaporation stage.
In optionally designing, connection shown in Figure 1 can be combined with other black liquor cooler, is used for adding the black liquor of the part prevapourising of liquid stream on the hot black liquor cooler.Fig. 5 show the part evaporation black liquor and stream be how to be led to liquid chiller HE1D and to be guided back evaporation stage I from this liquid chiller HE1D with the supply stream that flows to this grade or in the supply stream of himself.The black liquor that is cooled from liquid chiller HE1C is led to liquid chiller HE1D, before being supplied to evaporation stage I at black liquor via pipeline 10 it is further cooled off.Also liquid chiller HE1D and this level can be combined.
This evaporation equipment can also be revised in many ways, wherein black liquor and the evaporation stage of evaporation in the pipeline in carry out heat exchange between the black liquor that partly evaporated at least before, can carry out the prevapourising or the processing of certain form.This can carry out explicitly earlier with digestion equipment, or carries out in evaporation stage in evaporation process.This preliminary treatment can be by reducing pressure or carry out with increased viscosity by the black liquor that adds part evaporation, and the processing procedure of back is known " desulfurization (sweetening) ".Therefore, be led to first heat exchanger (black liquor of part evaporation is heated by hot black liquor) before in this first heat exchanger at the hot black liquor that from digestion process, obtains, can be directed to by at least one cooler (in this cooler, utilizing the black liquor in the cold water cooling heat exchanger) or by the pressure release groove or by above-mentioned both.By this way, the hot black liquor that obtains from digestion process carried out at least one cooling class carry out heat exchange with black liquor that partly evaporated at least, part evaporation in the evaporation stage of evaporation pipeline before.
The present invention can advantageously be employed in following mode: hot black liquor with the heat exchange operation each time that black liquor was carried out of part evaporation in be cooled at least 5-10 ℃ largely; And, be heated 5-10 ℃ at least in the heat exchange operation each time that black liquor and hot black liquor carried out of part evaporation.Far and away, black liquor can either be cooled by the fluid transfer between two-stage, also can be cooled by the circulating fluid in an evaporation stage.
Heat exchanger in this evaporation equipment is preferably tubing heat exchanger or heat-exchangers of the plate type, and wherein, hot black liquor is guided in a side of heat exchanger, is guided at the opposite side of heat exchanger through black liquor at least one evaporation stage, part evaporation.In this manner, carry out heat exchange by the indirect heat exchange in heat exchanger, and do not make these liquid mixing, and the methanol content of the black liquor that for example will evaporate remains unchanged.
The present invention is not limited to use a kind of like this evaporation equipment: in this evaporation equipment, has the evaporation stage that adds up to n in the evaporation pipeline, the reverse flow that described evaporation stage is set to be strict connects, the steam that is used to evaporate is directed to evaporation stage n-1 from evaporation stage n via a plurality of steam pipelines, or the like, and down to evaporation stage 1, and the hot black liquor that will evaporate from evaporation stage 1 via a plurality of feed-lines that are used to carry the black liquor of part evaporation, be led to evaporation stage 2 in the mode that is reverse flow with respect to vapor stream, or the like, and upwards to evaporation stage n.Yet it is favourable using strict reverse flow, because evaporation is what to carry out under the black liquor condition of minimum dry matter content level and MV minium viscosity for the first time, has guaranteed the high coefficient of overall heat transmission like this.
The present invention can change under the framework of claims in many ways.
Can be led to the pressure that black liquor with part evaporation reduces black liquor before carrying out heat exchange for the first time at for example black liquor.For example, owing to the steam that reduces to obtain of this pressure can be led to the evaporation pipeline in liquid vapour between the higher steam level mixes: for example, steam can mix with the liquid vapour of guiding to evaporation stage 5 from evaporation stage 6.If the black liquor that obtains from digestion process remains negative pressure, and keep for example 110 ℃ temperature, then its pressure can be lowered the temperature to provide 100-105 ℃, wherein, is mixed with the liquid vapour that keeps uniform temp by the steam that depressurization step obtained.Yet in most of advantageous embodiments, black liquor directly is guided the liquid chiller that does not make its flash through the heat of one or more recovery black liquor from digestion equipment under 110 ℃ temperature for example.This operation is favourable, because the flash meeting of black liquor is accompanied by the risk that forms foam and the bad separation of methyl alcohol.
Each heat exchanger unit (black liquor is cooled by the black liquor of part evaporation in described heat exchanger unit) can be made of one or more heat exchanger units that connect in the serial or parallel connection mode.
Among Fig. 1 to Fig. 3 the temperature of appointment be the representative instance that is used to implement the temperature levels of setting of the present invention.
Term " black liquor " is used for representing the black liquor from digestion process, and this black liquor does not carry out any evaporation level in each evaporation stage of evaporation pipeline, and is keeping the dry matter content level less than 30%.Yet, black liquor can be in advance through supercooling, adjusting (" desulfurization ") or other evaporated forms, for example by mechanical vapour compression, or utilize except by live steam or guide other steam the steam that the liquid vapour by each evaporation stage produces in turn in the evaporation pipeline.
Term " part evaporation black liquor " be used for representing the evaporation pipeline by live steam or successively guiding pass the black liquor of the liquid vapour of evaporation stage through at least one evaporation stage.
The present invention is particularly advantageous in evaporation by the black liquor that sulphate digestion obtained, and if sulphate digestion is based on needlebush, is mainly pine, then the present invention is more favourable.This trees comprises the extractable (soap) of higher level, and for the liquid of the soap that do not eliminate (desoap), described extractable is easy to cause the problem of bubbling.
Claims (20)
1. the method that is used for evaporating during the cellulose pulp manufacturing hot black liquor that obtains from digestion process, wherein black liquor is led to the multistage evaporation pipeline with at least five evaporation stages, it is characterized in that, the hot black liquor that will evaporate in described evaporation pipeline is cooled by carrying out heat exchange with the black liquor that partly evaporates, and is evaporated at least in part in the evaporation stage of black liquor in described evaporation pipeline of wherein said part evaporation.
2. the method for claim 1 is characterized in that, the black liquor of the evaporation of part of having been evaporated at least in part in described hot black liquor and first evaporation stage in described evaporation pipeline and second evaporation stage carries out heat exchange and is cooled at least twice.
3. method as claimed in claim 2 is characterized in that, described hot black liquor carries out heat exchange and is cooled at least three times with the partly black liquor of evaporation that has been evaporated at least in part in first evaporation stage, second evaporation stage and the 3rd evaporation stage.
4. method as claimed in claim 2, it is characterized in that, the black liquor of the described part evaporation that is used for carrying out heat exchange with described hot black liquor obtains from first evaporation stage, second evaporation stage, and the dry matter content level of the black liquor of wherein said part evaporation is increased from described first evaporation stage to described second evaporation stage.
5. method as claimed in claim 3, it is characterized in that, the black liquor of the described part evaporation that is used for carrying out heat exchange with described hot black liquor obtains from first evaporation stage, second evaporation stage and the 3rd evaporation stage, the dry matter content level of the black liquor of wherein said part evaporation is increased from described first evaporation stage to described second evaporation stage, and is further increased from described second evaporation stage to described the 3rd evaporation stage.
6. each described method in the claim 1 to 5 as described above is characterized in that, the black liquor that is used for carrying out with described hot black liquor the described part evaporation of heat exchange is recovered from the interior circulation of an evaporation stage.
7. each described method in the claim 1 to 5 as described above is characterized in that, is used for and black liquor that described hot black liquor carries out the described part evaporation of heat exchange is recovered from the circulation of the transmission between two evaporation stages.
8. each described method in the claim 1 to 5 as described above, it is characterized in that, the described hot black liquor that obtains from described digestion process is at least one cooling class of experience before the black liquor with the evaporation of described part carries out heat exchange, is evaporated at least in part in the evaporation stage of black liquor in described evaporation pipeline of wherein said part evaporation.
9. each described method in the claim 1 to 5 as described above, it is characterized in that, described hot black liquor with each heat exchange operation that black liquor carried out of described part evaporation in be cooled 5-10 ℃ at least, and the black liquor of described part evaporation is heated 5-10 ℃ at least in each heat exchange operation of being carried out with described hot black liquor.
10. each described method in the claim 1 to 5 as described above is characterized in that described heat exchange is undertaken by the indirect heat exchange in heat exchanger.
11. each described method in the claim 1 to 5 as described above, it is characterized in that, has the evaporation stage that adds up to n in the described evaporation pipeline, the reverse flow that described evaporation stage is set to be strict connects, the steam that wherein is used to evaporate is led to evaporation stage n-1 from evaporation stage n, and down to evaporation stage 1, and the described hot black liquor that will evaporate is led to evaporation stage 2 from evaporation stage 1 in the mode that is reverse flow with respect to vapor stream, and upwards to evaporation stage n.
12. be used for evaporating during the cellulose pulp manufacturing equipment of the hot black liquor that obtains from digestion process, wherein black liquor is led to the multistage evaporation pipeline with at least five evaporation stages, and wherein each evaporation stage all has: be used to supply the supply line that keeps the black liquor first dry matter content level, that will evaporate; And the export pipeline that is used for having been evaporated at least in part and having maintained at described evaporation stage the black liquor of the second higher dry matter content level, wherein said evaporation stage is provided with: in order to supply the supply line that keeps first vapor (steam) temperature and be used in the steam in the described evaporation stage; And be used for having used at described evaporation stage, the export pipeline that keeps the steam of lower second vapor (steam) temperature, it is characterized in that, first heat exchanger unit (HE1) is connected to first evaporation stage (I), described first heat exchanger unit has first inlet and first outlet of the heated side of leading to described heat exchanger unit, first inlet of wherein said first heat exchanger unit is connected to the partly export pipeline (20) of the black liquor of evaporation that is used for from described first evaporation stage (I), first outlet (21) of described first heat exchanger unit is connected to the partly intake pipeline (21) of the black liquor of evaporation that is used to be led to second evaporation stage (II), and described first heat exchanger unit has second inlet (11) and second outlet (10) of the cold side of leading to described heat exchanger unit, second inlet of described heat exchanger unit is connected to the hot black liquor that does not evaporate as yet in any evaporation stage, described second outlet is connected to the inlet that leads to described first evaporation stage (I).
13. equipment as claimed in claim 12, it is characterized in that, second heat exchanger unit (HE2) is connected to second evaporation stage (II), described second heat exchanger unit has first inlet and first outlet of the heated side that is connected to described second heat exchanger unit, first inlet of wherein said second heat exchanger unit is connected to the partly export pipeline (22) of the black liquor of evaporation that is used for from described second evaporation stage (II), first outlet (23) of described second heat exchanger is connected to the partly intake pipeline (23) of the black liquor of evaporation that is used to be led to the 3rd evaporation stage (III), and described second heat exchanger has second inlet (12) and second outlet (11) of the cold side of leading to described second heat exchanger unit, second inlet that wherein leads to described second heat exchanger unit is connected to the hot black liquor that does not evaporate as yet in any evaporation stage, the described hot black liquor that does not evaporate in any evaporation stage as yet at first is led to the cold side of described second heat exchanger unit via before described second outlet and being led to the cold side of described first heat exchanger unit (HE1) via feed-line (11).
14. equipment as claimed in claim 13, it is characterized in that, the 3rd heat exchanger unit is connected to the 3rd evaporation stage, described the 3rd heat exchanger unit has first inlet and first outlet of the heated side of leading to described the 3rd heat exchanger unit, first inlet of described the 3rd heat exchanger unit is connected to the export pipeline that is used for from the black liquor of described the 3rd evaporation stage, first outlet of wherein said the 3rd heat exchanger unit is connected to and is used to be led to the 4th evaporation stage (IV), the intake pipeline of the black liquor of part evaporation, and described the 3rd heat exchanger unit has second inlet and second outlet of the cold side of leading to described the 3rd heat exchanger, second inlet of described the 3rd heat exchanger unit is connected to the hot black liquor that does not evaporate as yet in any evaporation stage, the described hot black liquor that does not evaporate in any evaporation stage as yet at first was led to the cold side of described the 3rd heat exchanger unit before the cold side of cold side that is directed to described first heat exchanger unit via feed-line one by one and described second heat exchanger unit.
15. as claim 13 or 14 described equipment, it is characterized in that, described first evaporation stage (I), described second evaporation stage (II) and described the 3rd evaporation stage (III) that is associated connect with series system, wherein the black liquor that will evaporate in described evaporation stage is led to described second evaporation stage from described first evaporation stage via the heated side of described heat exchanger one by one, then be directed to described the 3rd evaporation stage, and can be directed to the 4th evaporation stage forward.
16. each described equipment in the claim 12 to 14 as described above, it is characterized in that, entrance and exit on the heated side of described heat exchanger is connected to a pipeloop in the evaporation stage, makes the black liquor recirculation of evaporating through the part of described evaporation stage by means of recirculation line (21b) by interior circulation.
17. each described equipment in the claim 12 to 14 is characterized in that as described above, the inlet that leads to the heated side of described heat exchanger is connected to the black liquor that will evaporate is delivered to evaporation stage subsequently from previous evaporation stage feed-line.
18. each described equipment in the claim 12 to 14 as described above, it is characterized in that, the hot black liquor that obtains from described digestion process is being led to first heat exchanger (HE1) before, be conducted through at least one cooler or pressure release groove or at least one cooler and pressure release groove, the black liquor of part evaporation is heated by described hot black liquor in described first heat exchanger (HE1).
19. each described equipment in the claim 12 to 14 as described above, it is characterized in that, described heat exchanger is tubing heat exchanger or heat-exchangers of the plate type, wherein the hot black liquor that does not evaporate in any evaporation stage as yet is guided in a side of described heat exchanger, and the black liquor that evaporates through the part of at least one evaporation stage is guided at the opposite side of described heat exchanger.
20. each described equipment in the claim 12 to 14 as described above, it is characterized in that, has the evaporation stage that adds up to n in the described evaporation pipeline, the reverse flow that described evaporation stage is set to be strict connects, the steam that wherein is used to evaporate is led to evaporation stage n-1 from evaporation stage n via steam pipeline, and down to evaporation stage 1, and the hot black liquor that will evaporate from evaporation stage 1 via the feed-line of the black liquor that is used for the part evaporation, be led to evaporation stage 2, and upwards to evaporation stage n in the mode that is reverse flow with respect to vapor stream.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE0602361-8 | 2006-11-07 | ||
| SE06023618 | 2006-11-07 | ||
| SE0602361A SE529386C2 (en) | 2006-11-07 | 2006-11-07 | Evaporating method for hot black liquor obtained from digestion process during production of cellulose pulp, involves cooling hot black liquor by heat exchange with black liquor partially evaporated in evaporation stage in evaporation line |
| PCT/SE2007/050786 WO2008057031A1 (en) | 2006-11-07 | 2007-10-26 | A method and equipment for the evaporation of black liquor that is obtained from a digestion process during the production of cellulose pulp |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN101535565A CN101535565A (en) | 2009-09-16 |
| CN101535565B true CN101535565B (en) | 2011-01-12 |
Family
ID=38267495
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN200780041461.1A Expired - Fee Related CN101535565B (en) | 2006-11-07 | 2007-10-26 | A method and equipment for the evaporation of black liquor that is obtained from a digestion process during the production of cellulose pulp |
Country Status (7)
| Country | Link |
|---|---|
| US (1) | US8888955B2 (en) |
| EP (1) | EP2079873B1 (en) |
| CN (1) | CN101535565B (en) |
| BR (1) | BRPI0718576B1 (en) |
| RU (1) | RU2418901C2 (en) |
| SE (1) | SE529386C2 (en) |
| WO (1) | WO2008057031A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2011102761A1 (en) * | 2010-02-17 | 2011-08-25 | Metso Power Ab | Method and apparatus for controlling incrustations in multi stage evaporation train for black liquor |
| CN102277769B (en) * | 2011-09-07 | 2013-03-06 | 宜宾丝丽雅集团有限公司 | Technology for heating and processing black liquor in alkali recovery |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3216788A (en) * | 1961-08-24 | 1965-11-09 | Owens Illinois Glass Co | Flash evaporation of pulp liquor to eliminate calcium salts |
| US4941946A (en) * | 1988-03-23 | 1990-07-17 | Metallgesellschaft Aktiengesellschaft | Process for decreasing the tendency to form deposits in plants for evaporating spent sulfite liquors |
| US4953607A (en) * | 1989-02-17 | 1990-09-04 | A. Ahlstrom | Multistage evaporating system |
| US4963231A (en) * | 1988-06-13 | 1990-10-16 | Ahlstromforetagen Svenska Ab | Method for evaporation of liquids |
| CN1067080A (en) * | 1992-04-15 | 1992-12-16 | 汪仲熙 | The low-loss and energy-saving recovery and steam-boiling technology for chemically making non-wooden pulp |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2840154A (en) * | 1954-04-27 | 1958-06-24 | Chicago Bridge & Iron Co | Multiple effect evaporator |
| US2942657A (en) * | 1957-05-28 | 1960-06-28 | Bowen Corp | Vapor compression evaporation |
-
2006
- 2006-11-07 SE SE0602361A patent/SE529386C2/en unknown
-
2007
- 2007-10-26 US US12/513,505 patent/US8888955B2/en not_active Expired - Fee Related
- 2007-10-26 WO PCT/SE2007/050786 patent/WO2008057031A1/en active Application Filing
- 2007-10-26 CN CN200780041461.1A patent/CN101535565B/en not_active Expired - Fee Related
- 2007-10-26 RU RU2009121572/12A patent/RU2418901C2/en not_active IP Right Cessation
- 2007-10-26 EP EP07835370.3A patent/EP2079873B1/en not_active Not-in-force
- 2007-10-26 BR BRPI0718576A patent/BRPI0718576B1/en not_active IP Right Cessation
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3216788A (en) * | 1961-08-24 | 1965-11-09 | Owens Illinois Glass Co | Flash evaporation of pulp liquor to eliminate calcium salts |
| US4941946A (en) * | 1988-03-23 | 1990-07-17 | Metallgesellschaft Aktiengesellschaft | Process for decreasing the tendency to form deposits in plants for evaporating spent sulfite liquors |
| US4963231A (en) * | 1988-06-13 | 1990-10-16 | Ahlstromforetagen Svenska Ab | Method for evaporation of liquids |
| US4953607A (en) * | 1989-02-17 | 1990-09-04 | A. Ahlstrom | Multistage evaporating system |
| CN1067080A (en) * | 1992-04-15 | 1992-12-16 | 汪仲熙 | The low-loss and energy-saving recovery and steam-boiling technology for chemically making non-wooden pulp |
Non-Patent Citations (2)
| Title |
|---|
| 欧成忠.板式-长管式蒸发器串联运行的几点认识.《中国造纸》.1992,(第5期),3-7. * |
| 黎振球 等.蔗渣黑液高浓蒸发特性的研究.《中国造纸学报》.1999,第14卷82-90. * |
Also Published As
| Publication number | Publication date |
|---|---|
| EP2079873A1 (en) | 2009-07-22 |
| US20100071862A1 (en) | 2010-03-25 |
| BRPI0718576B1 (en) | 2017-04-25 |
| CN101535565A (en) | 2009-09-16 |
| BRPI0718576A2 (en) | 2014-03-11 |
| SE0602361L (en) | 2007-07-24 |
| EP2079873B1 (en) | 2014-12-03 |
| SE529386C2 (en) | 2007-07-24 |
| US8888955B2 (en) | 2014-11-18 |
| RU2009121572A (en) | 2010-12-20 |
| EP2079873A4 (en) | 2013-05-15 |
| WO2008057031A1 (en) | 2008-05-15 |
| RU2418901C2 (en) | 2011-05-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1921281B1 (en) | Seawater desalinating apparatus using blowdown water of heat recovery steam generator | |
| US8512514B2 (en) | Method and system to generate steam in a digester plant of a chemical pulp mill | |
| US8808498B2 (en) | Heat recovery from spent cooking liquor in a digester plant of a chemical pulp mill | |
| RU2404316C2 (en) | Improved line systems for production of fibre, processes and techniques | |
| CN101948148A (en) | Energy-saving low-temperature multiple-effect seawater desalting device | |
| KR20030041854A (en) | Process and plant for multi-stage flash desalination of water | |
| US20210370196A1 (en) | Low Energy Ejector Desalination System | |
| CN101811743A (en) | Circulation evaporator | |
| CN101535565B (en) | A method and equipment for the evaporation of black liquor that is obtained from a digestion process during the production of cellulose pulp | |
| EP0623041A4 (en) | Evaporative concentration of clay slurries. | |
| CN1306942A (en) | Method and apparatus for preparing fresh water from sea water | |
| CN205045839U (en) | Thermodynamic system that steam turbine exhaust steam latent heat was used multipurposely | |
| JP5130302B2 (en) | Method for producing cellulose pulp with excellent energy efficiency in a continuous digester | |
| WO2016038247A1 (en) | Method of generating steam at a digester plant of a chemical pulp mill | |
| CN103030185B (en) | Low-temperature multi-effect sea water desalinization system | |
| RU2047675C1 (en) | Method of regeneration of technological solutions in viscose fiber production | |
| US4279126A (en) | Method of utilizing residual heat in the production of cellulose and an installation for carrying out the method | |
| CN201704094U (en) | Circulating evaporation device | |
| CN202988779U (en) | Low-temperature multi-effect seawater desalinization system | |
| RU2392453C2 (en) | System to produce make-up water at heat supply enterprises |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20110112 Termination date: 20201026 |